1. Field of the Invention
This invention relates to a process for remineralizing dental enamel in which solutions containing calcium and phosphate ions are mixed to form a metastable solution which is applied to dental enamel, resulting in remineralization of the dental enamel and efficacy against caries.
2. The Prior Art
It is well known in the dental art that dental caries begin as a subsurface demineralization ("white spots") of the dental enamel and that remineralization or recalcification may be of importance in retarding or arresting dental caries. However, heretofore no method was known by which a member of the general public could conveniently effect remineralization of subsurface dental enamel. Ruthrauff; U.S. Pat. No. 1,222,144, issued Apr. 10, 1917 teaches acidic dentifrice compositions for remineralizing tooth enamel comprising a soluble calcium salt, and an agent for more effectively causing the solution to permeate and completely fill up the minute spaces in the tooth surface. Klein et al; U.S. Pat. No. 2,154,168; issued Apr. 11, 1939 discloses dentifrices containing calcium and phosphate ions and having a pH of from about 5 to about 10. Rubin et al; U.S. Pat. No. 3,679,360; issued July 25, 1972, discloses a method, the purpose of which is to deposit calcium phosphate from a gel medium onto the tooth surface. The surface on which calcium phosphate growth is desired is prepared (as by roughening) and the tooth and coatings are covered by a suitable cap for several days while the remineralization takes place. Warner Lambert's British Pat. No. 1,090,340 discloses the use of slightly alkaline supersaturated calcium phosphate solutions to effect some degree of emanel remineralization.
In spite of the above described prior art remineralization attempts, there is a continuing need for compositions and methods by which remineralization can be conveniently and effectively accomplished. Abandoned U.S. application Ser. No. 297,517, filed Oct. 13, 1972, Robert John Grabenstetter and John Augustus Gray, III, entitled "PROCESSES AND COMPOSITIONS FOR REMINERALIZATION OF DENTAL ENAMEL" and its subsequently filed related applications (Ser. No. 438,973, filed Feb. 4, 1974 and Ser. No. 561,830, filed Apr. 2, 1975, now both abandoned) teaches a method of remineralizing subsurface dental enamel in which two compositions containing, respectively, a cation and an anion, such as calcium ion and phosphate ion, are sequentially applied to the dental enamel. This method, while successful, requires sequential application of the respective solutions. The present invention, on the other hand, provides a method by which subsurface dental enamel can be mineralized by the application of one solution to the tooth surface.